Typical high-performance communication cables in widespread use contain twisted pairs for transmitting electrical communication signals or optical fibers for transmitting optical communication signals, but usually not both. Engineering requirements for optical communication cables are typically very different than engineering requirements for electrical communication cables.
Communication cables that successfully transmit electrical communication signals and comply with industry specifications for electrical signals, such as ICEA S-84-608, ordinarily are designed to manage cabling forces that the twisted pairs experience in connection with installation, pulling, thermal expansion, and other conditions. This management can include translating cabling forces to cross sectional areas of the cables that are separated from the twisted pairs. Meanwhile, communication cables that successfully transmit optical communication signals and comply with industry specifications for optical signals, such as GR-20-Core, ordinarily are designed to manage cabling forces that the optical fibers experience in connection with installation, pulling, thermal expansion, and other conditions. This management can include translating cabling forces to cross sectional areas of the cables that are separated from the optical fibers.
However, for a cable containing optical fibers and twisted pairs, the translation of cabling forces is typically complicated by an objective of avoiding a translated force from encroaching on the optical fibers or the twisted pairs. Moreover, twisted pairs and optical fibers are sensitive to different types of stress and strain and further can generate forces that can interfere with one another.
Accordingly, need exists for a technology that supports disposing optical fibers and twisted pairs in a single cable while managing cable forces to achieve robust optical and electrical signal performance. Need further exists for a composite cable that can be deployed along a railway or other transportation line and meet specialized railway and transportation objectives. A capability addressing such need or some other related deficiency in the art could facilitate transmitting quality optical communication signals and quality electrical communication signals over a compact cable.